Le complexe Djruchula-Koudaro au sud Caucase (Géorgie). Remarques sur les assemblages lithiques pléistocènes de Koudaro I, Tsona et Djruchula

Georgia yielded numerous Middle Paleolithic sites dated of the end of Middle Pleistocene and Upper Pleistocene, located at the foot of the Great Caucasus barrier. Several cultural groups are based on local technical trends or on behaviours coming from other areas (Near-East, Zagros, Eastern Europe). One of these, named Djruchula-Koudaro, groups sites from the Imereti and southern Ossetie areas (north and north-west of Georgia). It yields lithic assemblages with common traits, such as the proportion of blades and the use of bifacial retouches, in particular to shape the tip of elongated artefacts. If the origin of these characters leads of think to a possible link with the Near-East, another hypothesis, developed in the 1960s–1970s by Georgian researchers, proposes a relationship between the Caucasian Acheulian and the Early Middle Paleolithic. In this way, the study of artefacts of reference sites of this complex (Koudaro, Tsona and Djruchula caves) has launched a discussion about the beginning of the Middle Paleolithic in southern Caucasus through the laminar flaking, trying to find the part of local technical behaviours and influences born from contacts or population movements from neighbouring areas.La Géorgie livre de nombreux gisements du Paléolithique moyen qui permettent d'appréhender les modesd'occupations humaines à la fin du Pléistocène moyen et début du Pléistocène supérieur au pied de la barrière montagneuse du Grand Caucase. Plusieurs complexes industriels sont basés sur des traits techniques originaux ou emprunts d'influences régionales (Proche-Orient, Zagros, Europe orientale). Un d'entre eux, le groupe Djruchula-Koudaro rassemble des sites de la région d'Imereti et d'Ossetie du Sud (Nord et Nord Ouest du pays) avec des assemblages lithiques présentant des caractéristiques morpho-techniques communes avec une tendance laminaire très marquée et l'emploi de retouchesbifaciales, notamment pour appointer les supports allongés. Si l'origine de ces traits permet indéniablement de penser à une influence probable du Proche-orient, l'hypothèse, développée dans les années 1960-1970 par des chercheurs géorgiens proposant également une filiation locale à partir du substrat acheuléen du Caucase, n'est pas à exclure. C'est dans ce cadre que l'examen ou le ré-examen de séries lithiques issues des sites éponymes de ce complexe (grotte de Koudaro, Djruchula et Tsona) permet de discuter de cette genèse laminaire au Paléolithique moyen dans le Sud-Caucase,en essayant de faire la part d'un "endémisme" techno-culturel et des influences nées de contacts ou de mouvements populationnels depuis les zones avoisinantes

Age and date for early arrival of the Acheulian in Europe (Barranc de la Boella, la Canonja, Spain)

The first arrivals of hominin populations into Eurasia during the Early Pleistocene are currently considered to have occurred as short and poorly dated biological dispersions. Questions as to the tempo and mode of these early prehistoric settlements have given rise to debates concerning the taxonomic significance of the lithic assemblages, as trace fossils, and the geographical distribution of the technological traditions found in the Lower Palaeolithic record. Here, we report on the Barranc de la Boella site which has yielded a lithic assemblage dating to ,1 million years ago that includes large cutting tools (LCT). We argue that distinct technological traditions coexisted in the Iberian archaeological repertoires of the late Early Pleistocene age in a similar way to the earliest sub-Saharan African artefact assemblages. These differences between stone tool assemblages may be attributed to the different chronologies of hominin dispersal events. The archaeological record of Barranc de la Boella completes the geographical distribution of LCT assemblages across southern Eurasia during the EMPT (Early-Middle Pleistocene Transition, circa 942 to 641 kyr). Up to now, chronology of the earliest European LCT assemblages is based on the abundant Palaeolithic record found in terrace river sequences which have been dated to the end of the EMPT and later. However, the findings at Barranc de la Boella suggest that early LCT lithic assemblages appeared in the SW of Europe during earlier hominin dispersal episodes before the definitive colonization of temperate Eurasia took place.The research at Barranc de la Boella has been carried out with the financial support of the Spanish Ministerio de Economı´a y Competitividad (CGL2012- 36682; CGL2012-38358, CGL2012-38434-C03-03 and CGL2010-15326; MICINN project HAR2009-7223/HIST), Generalitat de Catalunya, AGAUR agence (projects 2014SGR-901; 2014SGR-899; 2009SGR-324, 2009PBR-0033 and 2009SGR-188) and Junta de Castilla y Leo´n BU1004A09. Financial support for Barranc de la Boella field work and archaeological excavations is provided by the Ajuntament de la Canonja and Departament de Cultura (Servei d’Arqueologia i Paleontologia) de la Generalitat de Catalunya. A. Carrancho’s research was funded by the International Excellence Programme, Reinforcement subprogramme of the Spanish Ministry of Education. I. Lozano-Ferna´ndez acknowledges the pre-doctoral grant from the Fundacio´n Atapuerca. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Premières phases de peuplement dans le Caucase (étude des assemblages lithiques des sites géorgiens de Dmanissi (Pleistocène inférieur), de Koudaro I et de Tsona (Pleistocène moyen))

La découverte du site de Dmanissi (Géorgie), daté de 1,77 Ma, a bouleversé les théories sur les premières phases de peuplement en Eurasie. L étude des artefacts est capitale pour la compréhension des comportements des hominidés du Pléistocène hors Afrique. Ce travail a été consacré à l étude de la totalité de l assemblage, ainsi qu au mode d acquisition des matières premières. Les roches utilisées sont locales. La présence de nucléus et d éclats montre que toutes les phases d un débitage sont présentes sur place. Koudaro I et Tsona sont les seuls sites à avoir livré des traces d occupations stratifiées qui peuvent être rattachées à de l Acheuléen. L analyse de ces assemblages a permis de préciser les caractéristiques originales, témoins peut-être d une expansion septentrionale de vagues humaines ou d une diffusion culturelle en provenance d Afrique via le Proche Orient, ainsi que le rôle du Grand Caucase comme barrière sur la mobilité et les stratégies comportementales des ces occupants.The discovery of Dmanisi (Georgia), dated 1.77 million years, has changed the approach to the theory about the first human settlement in Eurasia. This study gives us the opportunity to follow the behavior of the pleistocene hominids outside Africa. This work includes studies of the whole collection of the lithic assemblage as well as the determination of the raw material. Hominids have mainly used local volcanic rocks. Existence of cores and flakes show that tools have been knapped on the site. Kudaro I and Tsona are nowadays the rare archaeological sites, found in stratigraphy, from the acheulean period. The study of this stone industry gives us the opportunity to reveal its original characteristics, that can be explained on one hand by the human expansion towards northern regions, and on the other hand by a spreading of the acheulean culture from Africa, through the Levant, and also by the presence of the Great Caucasus as a barrier for behavioral strategy and mobility of the hominids.PARIS-Museum Hist.Naturelle (751052304) / SudocSudocFranceF

From the Mesolithic to the Chalcolithic in the South Caucasus: New data from the Bavra Ablari rock shelter

The site of Bavra-Ablari is a Mesolithic-Chalcolithic rock shelter, located on the Javakheti plateau in the valley of a tributary of the Kura River, in southern Georgia. Excavations have been carried out by a Georgian-French team since 2012 and have shed light on processes that took place during the Early Holocene. The Mesolithic layer of the site shows an occupation, not yet fully excavated, which will provide important chrono-cultural information about the exploitation of the mountainous areas during the ninth millennium BCE. The Neolithic occupation chronologically matches the first evidence of agricultural society in the Near East during the sixth millennium BCE, and is characterised by a combination of Neolithic and Mesolithic features. The Chalcolithic layer produced a significant collection of material that supports a re-occupation of the highlands during the fifth millennium, as well as the development of subsistence strategies adapted to this environment

Hominin occupations at the Dmanisi site, Georgia, Southern Caucasus: Raw materials and technical behaviours of Europe’s first hominins

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Histoire de la végétation et occupation du Plateau de Samsari-Javakheti (Géorgie-Petit Caucase) depuis la fin du Tardiglaciaire.

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New 40Ar/39Ar, unspiked K/Ar and geochemical constraints on the Pleistocene magmatism of the Samtskhe-Javakheti highlands (Republic of Georgia)

International audienceThe Samtskhe-Javakheti volcanic plateau (Republic of Georgia) is the northernmost and youngest expression of the magmatism following the Arabia-Eurasia collision. Here, we present whole rock elemental and twenty-one new unspiked K/Ar and 40Ar/39Ar ages for the volcanic sequence well exposed east of the plateau. Based on our new radio-isotopic ages, we have identified three magmatic episodes. The oldest one (2.84–1.08 Ma), corresponding to the “Javakheti plateau s.s.”, is mainly constituted of medium-K alkaline mafic lavas (basalt, basaltic trachyandesite) and of intermediate composition domes (dacite). The more recent volcanic activity has constructed an impressive N–S trending volcanic ridge (Samsari s.s.) composed of evolved rocks (medium-K dacite to rhyolite). Within this ridge, two main periods of activity could be depicted: Middle Pleistocene (439–189 ka) and Late Pleistocene (90–13 ka). The youngest activity is restricted to the northern edge of this prominent magmatic structure and linked to the Tavkvetili volcano activity. According to these young ages, this area can be considered as a potential zone of volcanic hazards. The oldest volcanic activity shaping the Javakheti plateau is distributed between major strike slip faults in pull-apart position. The emplacement of the volcanism is controlled by a localized upper crustal extension. This is particularly outlined by the N–S linear array of domes that constitutes the Samsari ridge. This volcanic structure emplaced indeed on top of two major N–S faults that have probably played a key role to control the Middle to Late Pleistocene volcanism. The new 40Ar/39Ar ages date between 2.32 and 1.54 Ma the fauna assemblage of the Tsalka paleontological site. Rocks from the Samtskhe-Javakheti volcanic plateau derived from a low degree of melting of a metasomatized lithospheric mantle source (spinel facies). Except the obsidians from the Chickiani dome, they all derived from this source and evolved following a crystallization sequence involving mainly clinopyroxene, garnet, and/or amphibole. A crustal contamination component modified the composition of the youngest products (Samsari ridge rocks). According to the geochemical signature of these rocks, it seems that the magmatism does not fit with models involving asthenospheric upwelling in this region

Multiple origins of Bondi Cave and Ortvale Klde (NW Georgia) obsidians and human mobility in Transcaucasia during the Middle and Upper Palaeolithic

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